A custodial worker cleans the floor at dawn at the newly built One World Observatory at One World Trade Center on the day it opens to the public on May 29, 2015 in New York City. The observation deck sits atop the 104-story skyscraper at the former site of the Twin Towers and is expected to become one of Manhattan's top tourist attractions. (Photo by Spencer Platt/Getty Images) *** BESTPIX ***(Credit: Getty Images / Spencer Platt)